ES2323078T3 - INFUSION UNIT - Google Patents

Abstract

Infusion unit for the preparation of infusions, in particular espresso coffee, by means of infusion powders, comprising - a stationary piston (43), a mobile chamber (46) and a mobile piston (48) concentric to the mobile chamber, which can act together for the preparation of said infusion by means of said powders and to generate a powder pellet used, said mobile piston (48) being arranged to move relative to the mobile chamber (46) to prepare said powder pellet used for its expulsion from said infusion unit by means of a mechanically activated ejection device (49); characterized in that - said infusion unit comprises a plate (45) associated with movement means (55, 65, 66) arranged to move said plate, - said chamber comprises at least one elastic connecting element (71) having a certain stiffness and that it is arranged to connect said camera with said plate in order to induce movement of said camera together with said plate and to allow relative movement of said camera with respect to said plate, and - said ejection device is mechanically activated by the relative movement of said plate with respect to said chamber.

Description

Infusion unit

Technical field

The present invention relates to a unit of infusion for the preparation of infusions, to a machine infusion and the procedure to manufacture the unit of infusion.

In particular, the present invention relates to a unit for so-called super-automatic type machines vertical presenting a device to expel ground coffee used, to the corresponding vertical type machine and to procedure to manufacture the infusion unit.

Although the following description is made reference to vertical type machines, in which the pressing of the substance to prepare the infusion is done along a vertical axis or near the vertical axis, in a range of some degrees, the present invention can also be applied to machines of horizontal infusion in which, as is known, the pressing is performed along a substantially substantially axis horizontal, or to machines that have an intermediate orientation between a vertical axis and a horizontal axis.

Prior art

Machines and units are known in the art infusion for the preparation of infusions. In particular it know machines, for example super-automatic type machines vertical, comprising devices for the expulsion of dusts Infusion already used.

For example, a device for the expulsion of ground coffee already used that is applied to a vertical machine Coffee preparation is known from EP publication 0528758. The known machine comprises two opposite pistons, a upper piston that is stationary and a lower piston, a cylinder associated with the lower piston and which can form a chamber with the same, and an ejection arm that has a first end  that pivots towards the cylinder.

During the infusion stage, the cylinder, guided by a rotating shaft that has a rotating shaft outside of the cylinder, lower piston strip in the direction of the piston stationary to create an infusion chamber formed by the stationary piston, cylinder and lower piston.

After pressing the ground coffee and the corresponding infusion through a flow of pressurized water, the cylinder is guided in a direction opposite to the stationary piston pulling the piston itself with it and holding the arm of expulsion in a resting position.

The lower piston movement ends before that the movement of the cylinder due to appropriate stops fixed to the structure, so the cylinder continues its movement until that the lower piston head, which has a convex shape, exit the cylinder, which also has convex edges, to align the lower piston head with the cylinder edges and for cause the emersion of the powders used.

At the end of the movement, the ejection arm Rigid type, which has a concave spatula in a second end, it activates and performs an arc movement (pendulum type movement) around a pivot to eject the powders used that are on the convex head of the piston.

In particular, the ejection arm comprises a lever protruding from the pivot on which the first pivots end so that a first projecting element, fixed to the base of the structure, at the end of the cylinder movement, can activate the rotation of the lever and the ejection arm connected to the same.

In a next stage, when the cylinder rises, the lever is directed towards a second projecting element, fixed in one side of the structure, arranged to force a rotation in the opposite direction of the lever and arm to restore the resting position of the ejection arm.

A first problem of this prior art is that the expulsion mechanism comprises elements associated with the cylinder: the arm, the pivot and the lever; elements associated with the base of the structure: a first projecting element; elements associated to the sides of the structure; a second element outgoing; elements that, being associated with several parts of the machine, make a device calibration complex that could be necessary, for example, due to wear and tear of the protruding elements and / or lever that acts in conjunction with the protruding elements and / or the spatula.

Obviously, this problem is compounded by the fact that the area where the lever and the elements work outgoing, usually includes ground coffee mixed with water which is, as is known, highly abrasive.

An additional problem with this prior art is that it requires forming the piston with a convex head and the cylinder, analogously, with convex edges to prevent the ground coffee used to accumulate on the piston head and / or on the edges of the cylinder.

Obviously, as you can easily understand one skilled in the art, a curved shape of the piston head it is not optimal to obtain a uniformly distributed pressure on the infusion powders and, therefore, to obtain a Good infusion

A more general additional problem of this prior art is related to the fact that the movement of cylinder and piston is carried out by means of devices that they are not aligned with them, so normally driving forces are not balanced and this causes the wear and tear of the moving parts, which are also not balanced.

Other publications are also known related to vertical machines where a mechanical device for the expulsion of powders used.

For example, from the EP publication 0298544 an infusion machine is known in which it is provided an ejection device whose movement, a movement of type pendulum, is associated with a corresponding movement of one of the pistons

An additional example is described in the EP publication 0756843 in which the ejection device performs a transverse movement of the pistons and requires the support of a plurality of mechanical cams and a system of levers in order to synchronize the movement of the device with the one with the pistons.

Still another example is known from the EP 0299399 publication that reveals a configured vertical machine to expel the powders used by hot water.

Such types of solutions seem particularly different from the solution provided according to the present invention

The applicant states that all solutions known are particularly complex and difficult to calibrate, or they are ineffective since they do not guarantee a perfect extraction of powders used

Summary of the Invention

The object of the present invention is a unit of infusion for a suitable infusion machine to solve the above problems in a simple and effective way, and to avoid possible wear and tear due to dusts and liquids present in the machine.

A further object of the present invention is a device for expulsion of used powders that is Easy to manufacture and suitable to allow the use of pistons that Present a flat head.

Another object of the present invention is a infusion unit and a corresponding machine in which the movement of moving elements, such as the camera and the piston, be controlled axially with respect to the chamber and the piston.

Such an object is achieved by a unit of infusion and an infusion machine that presents the characteristics set forth in the subsequent claims.

The present invention also relates to a manufacturing process of the claimed unit.

The claims are an integral part of the teachings of the present invention.

According to a preferred embodiment, the unit of Infusion comprises, in addition to a mobile infusion chamber, a plate elastically connected to the infusion chamber of so that such an elastic connection can induce the movement of the chamber into the infusion unit or allow relative movement between the camera and the plate.

According to a preferred embodiment of this type, the infusion unit comprises an ejection device that is mechanically activated by the relative movement between the chamber and plate to expel the dusts used.

According to an additional feature of the present invention, the movement of the plate and the chamber associated is obtained by devices located in a position centrobaric with respect to the plate and the chamber.

Brief description of the drawings

These and other additional features of the The present invention will become more apparent from the following. detailed description of preferred embodiments provided to mode of non-limiting examples with reference to the drawings attachments in which the components designated with them or similar reference numbers indicate components that present the same functionality and construction, or similar, and in which:

fig. 1 shows a general diagram of a super automatic machine for the preparation of infusions;

fig. 2 shows an infusion unit according to the invention in a first stage of an infusion cycle;

fig. 3 shows an infusion unit according to the invention in a second stage of the infusion cycle;

fig. 4 shows an infusion unit according to the invention in a third stage of the infusion cycle; Y

fig. 5 shows a perspective view of the ejection device according to the invention mounted on the unit infusion.

Best way to carry out the invention

With reference to fig. 1, a machine 10 suitable for the preparation of infusions (machine), for example a vertical type super automatic machine for the preparation of espresso coffee, referred to from this moment to greater clarity in the description, includes a boiler 12, of a known type, which can heat and keep under pressure a determined amount of liquid, such as water, a unit 14 infusion and at least one dispensing tap 15.

The dispensing bobbin 15, of known type, it is connected to the infusion unit through ducts 18 and you can dispense the infusion in one or more bowls or cups of coffee as a result of the preparation of the infusion through the unit 14 infusion.

The infusion unit 14 is connected, in one known way, to boiler 12 and is suitable for receiving water hot pressurized from boiler 12 through ducts 19, for example flexible ducts of a known type, and for prepare, for example, coffee by a generic infusion cycle described below and maintained as a reference for greater clarity in the description and that will be described later in the description of the operation of the machine 10.

The generic infusion cycle comprises, by example, the following stages:

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fill in with infusion powders, for example ground coffee, a cavity or cylinder, for example an infusion chamber, comprised in the infusion unit (load);

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close the cylinder using two pistons, press the ground coffee and supply pressurized hot water for a certain time (at approximately 90 ° C) to ground coffee through, for example, filters placed on the piston head and ducts inside the pistons (infusion);

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release the pistons and eject the ground coffee, at that time used (powders used), by the movement of a device mechanical expulsion (expulsion).

The infusion unit 14 (unit) comprises first, in the preferred embodiment, a first piston 43, by example a stationary type piston (figs. 2, 3, 4) and a structure 41 (unit structure) that can support, of a known manner, various components or devices of unit 14 and of the first piston 43 (stationary piston).

The structure also comprises a plurality of stems 61 (vertical rods), which have for example a circular cross section and that can guide the movement of various components or mobile devices of unit 14, such and as will be described later in detail.

The stationary piston 43, of a known type, it comprises a filter 33 and an inner duct 38 coupled to the ducts 18 connected to the dispensing bobbin 15 (fig. one).

Preferably, the stationary piston 43 is formed to transfer the infusion, during the stage of infusion, from the infusion unit to tap 15 of dispensing

Unit 14 further comprises a motor 66 and a mobile plate 45 (plate) (figs. 1, 2, 3, 4) that can be moved alternatively by the engine 66.

The plate, which has for example a shape rectangular, it comprises a plurality of cavities 53 (fig. 5) located at the upper ends of the plate 45 and coupled to the stems 61 (figs. 1, 2, 3, 4); the cavities 53 are arranged to allow plate 45 to slide along of the stems 61 of the structure 41.

The mobile plate 45 further comprises an element Coupling which, in the preferred embodiment, is centrobaric with respect to plate 45 and is associated with a Endless screw 65, which is also centrobaric with respect to the plate 45 and which is operated in a known manner by the motor 66 through a coupling gear.

According to the present embodiment by way of example, the mobile plate 45 can alternately move along the stems 61 to allow the execution of several stages of the cycle infusion, as will be described later in detail.

The motor 66, for example an electric motor of a known type is controlled, in a known way, to make turn the worm 65 clockwise or counterclockwise and, in the preferred embodiment, is associated with an absorption detector 67 of adapted current to determine the motor block if the motor 66 determines an overcurrent absorption default

Unit 14 also comprises a chamber 46 of infusion and a second piston 48, both being, for example, of type mobile.

The infusion chamber 46 (mobile camera) comprises, in the preferred embodiment, three elastic elements 71 arranged triangularly around the second piston 48 and in a centralbaric position with respect to plate 45 and the chamber 46; the elastic elements 71 have a stiffness determined and are shaped to mechanically connect the plate 45 mobile with 46 mobile camera.

The elastic elements 71 comprise, by example, cylindrical pressure springs of a known type housed in suitable seats, of a known type, which they provide spring pressure only in one direction; also, chamber 46 comprises, for example, cavities 63 (fig. 5) suitable to allow the camera itself to slide length of the stems 61 (figs. 1, 2, 3, 4) of the structure 41. The mobile camera 46 (camera), thanks to the connection established by the elastic elements 71 (springs), can be guided in the movement by the mobile plate 45 so that the alternative movement of the mobile plate 45 mainly induces the movement of the mobile camera 46 during the infusion cycle, as is will describe later in detail.

The mobile chamber 46 comprises a surface 72 inside, preferably with a cylindrical cross section, and an upper surface 73 which is preferably a surface associated plane, on one side of chamber 46, to one or more ducts 75 drainage, known for themselves, and aligned with the same.

The mobile camera 46 also comprises an element 78 support, of a known type, which can support and move the 48 mobile piston mainly together with the movement of the chamber mobile during the infusion cycle, as will be described subsequently in detail, and an annular feed chamber 74, of a known type, connected to the boiler 12 through the ducts 19 and that can introduce water into the mobile piston 48 hot pressurized during the infusion stage.

Finally, the mobile camera 46 comprises, preferably associated with the support element, a first element 79 stop (first stop), which you can limit, as will describe later in detail, the movement of the piston 48 mobile with respect to the mobile camera 46 that occurs during the infusion cycle

The mobile piston 48, concentric to the chamber mobile, comprises, in the preferred embodiment, a head 80, of a known type, and a rod 85 which, in the preferred embodiment, It has a cylindrical shape and is aligned with the screw 65 without finish.

The rod has a first end fixed to the head 80 in its centralbaric position and a second associated end to a second stop element 89 that can limit, as will be described later in detail, both the movement of the mobile piston 48 with respect to the mobile chamber 46, as the movement of the mobile camera 46 itself that occur during the infusion cycle.

The head 80 comprises a filter 83, of one type known, and is connected, in a known way, to camera 74 annular supply which in turn is connected to the boiler 12.

The rod 85 is associated with an element 81 elastic, for example a cylindrical pressure spring of one type known to have a first end fixed to the first stop 79 and a second end fixed to the second stop 89; element 81 elastic (spring), associated with the mobile piston 48, has in general, in the preferred embodiment, less stiffness than total stiffness of the springs 71 associated with the mobile camera 46 and is shaped to allow relative movement of the mobile piston 48 with with respect to the mobile camera 46 that occurs during the cycle of infusion, although it guarantees, thanks to the difference in stiffness, the movement of the mobile camera 46 together with mobile plate 45.

The mobile piston 48 can press the powders, inside the mobile chamber 46 and with the help of piston 43 stationary, to obtain the infusion.

The mobile piston 48, during the movement relative to mobile camera 46, you can also prepare the expulsion of the powders used, as will be described later in greater detail.

Finally, the infusion unit 14 comprises a mechanical ejection device 49 (ejection device) which can expel powders from unit 14 itself used

The ejection device 49 is shaped, in the preferred embodiment, as a lever presenting a fulcrum 91 (fig. 5) and a drive arm and an arm resistance, respectively 93 and 97, and can pass from a first position (rest position) to a second position (position of ejection) following a driving force applied to the arm drive.

In particular, fulcrum 91 pivots by means of a first pivot 96 towards a wall 47 fixed to or comprised in the mobile camera 46; the drive arm or first arm 93, to which is applied outside the drive, pivots, by means of a second pivot 95, towards plate 45; the resistance arm or second arm 97 is associated with a spatula 99 shaped to expel the dusts used.

More particularly, the relative movement of the mobile plate 45 with respect to mobile camera 46, movement which is possible, as will be described later in detail, thanks to springs 71 (figs. 4, 5), you can apply the force of drive to the first arm 93 to cause movement at along a circumferential arc of the second arm 97 associated with the spatula 99.

In an even more preferred embodiment, the spatula 99 comprises a scraper element 100 that can eject really the powders used, and first and second elements of sliding, respectively 109 and 106. In this embodiment, the second arm 97 comprises a cavity 107, longitudinal to the arm direction 97; the first elements 109 of sliding, for example rollers of a known type, are shaped to slide into the cavity 107 and are willing to unhook or set non-rigidly the connection between the spatula 99 and the arm 97 and to allow a limited displacement in the longitudinal direction of the spatula 99 with respect to arm 97.

However, in this embodiment, chamber 46 mobile comprises or is associated with a wall that has a cavity 76, preferably horizontal, and the second elements 106, for example a roller of a known type, they are shaped to slide into the cavity 76 horizontal.

The combination of cavity 107 of arm 97 and of the cavity 76 associated with the mobile camera 46 with the elements of sliding, respectively 109 and 106, of the spatula 99 can determine, as an expert can easily understand in the matter, a substantially horizontal movement of the spatula 99 and, consequently, of the scraper element 100 during the second arm movement 97.

In the preferred embodiment, element 100 scraper comprises a coating or brush 100a and a component Rigid 100b placed in sequence at the end of the second arm 97.

The coating 100a can make contact, mainly, with the surface 48 of mobile piston, and the rigid component 100b can make contact primarily with the powders used during the expulsion of ground coffee already used, so that the coating has the function main to clean the surface of the piston and component 100b rigid has the main function of performing the expulsion.

The operation of the machine 10 described Previously it is as follows.

Taking the infusion cycle as a reference generic, in a first stage (loading stage), exemplified in fig. 2, plate 45, chamber 46 and mobile piston 48 are in a relatively fixed and determined position, and the piston 43 stationary is located at a predetermined distance from the upper surface 73 of chamber 46 as far as possible, to through charging devices of a known type, enter a determined amount of infusion powders in the cavity obtained by means of the chamber 46 and the mobile piston 48.

During this stage, the springs 71 between the plate 45 and chamber 46 and spring 81 associated with mobile piston 48 They are at rest.

In a second stage (infusion stage), exemplified in fig. 3, plate 45, chamber 46 and piston 48 mobile move in the direction of the stationary piston 43, maintaining a relatively fixed and determined position, due to that, as experts in the field can easily understand material, springs 71 and spring 81 are not subject to No compression effort.

This stage can be described as the combination of two elementary stages, first of all a pressing stage and secondly, a real infusion stage.

In particular, in the pressing stage, the chamber 46 moves the mobile piston 48 by the element 78 of support in the direction of the stationary piston 43 to create a closed cavity or infusion chamber bounded by the surface 72 inside the chamber 46 and by the stationary piston and the piston  mobile, 43 and 48 respectively.

In addition, during this first stage, the springs 71 between plate 45 and chamber 46, and spring 81 associated with 48 mobile piston, they are at rest.

In the preferred embodiment, the movement of the plate 45, chamber 46 and mobile piston 48, ends when, as a result of the pressing exerted on the infusion powders, the current absorption detector 67 (figs. 1, 3) detects, by example, a corresponding predetermined current absorption to a predetermined pressing of the infusion powders, and stops the engine 66.

Once the pressing is finished, it activates a pressurized hot water flow from boiler 12 up to the head 80 of the mobile piston 48 in a manner known to get, thanks to the passage of the liquid through the chamber of infusion and stationary piston 43, the dispensing of the infusion through the dispensing bobbin 15 (stage of real infusion).

This stage has a duration of time normally determined according to the type and characteristics of the Infusion to be prepared.

At the end of this stage, the infusion powders they become a pill of used powders that should expel

In a third stage (expulsion stage), exemplified in fig. 4, plate 45, chamber 46 and piston 48 mobile move in a direction opposite to the position of the 43 piston stationary.

This stage can be described as the combination of three elementary stages in sequence: a first and a second elementary step away from piston 43 stationary and a third stage of actual expulsion of dusts used

During the two elementary stages, the engine 66, after the reversal of the rotating movement, move the plate 45 in a direction opposite to the position of the piston 43 stationary.

In the first step away, the plate 45, chamber 46 and mobile piston 48 maintain a position relatively fixed and determined and springs 71 and spring 81 They are not subjected to any compression effort.

The first stage of withdrawal ends when the head 80 of the movable piston makes contact with the screw 65 without finally, so that the movement of the mobile piston 48 stops.

In the second stage of estrangement, being the spring stiffness 81 lower than that of springs 71 which connect plate 45 and camera 46, plate 45 and camera 46 they continue their movement, while spring 81 is compressed and a corresponding movement of the mobile piston 48 is initiated with with respect to the chamber 46. This relative movement can cause the used powder tablet leaves from the surface 73 upper chamber 46.

The second stage of withdrawal ends when the first stop 79, associated with the chamber 46, makes contact with and stops by the second stop 89 associated with the mobile piston 48; this condition corresponds to the alignment of head 80 of the mobile piston 48 with the upper surface 73 of the chamber 46.

In the actual ejection stage, the engine 66 continues moving plate 45 while chamber 46, which is locked by contact with stops 79 and 89, you can compress the springs 71 connecting plate 45 and chamber 46 by inducing or activating thereby a corresponding movement between the plate 45 and the chamber 46; the corresponding relative motion applies the force drive to the first arm 93 and causes the movement of the second arm 97 and that of the associated spatula 99, that is, it makes the ejection device 49 changes from the rest position to the ejection position. The movement of the spatula 99 in this change stage can cause the expulsion of the tablet powders used from the head 80 of the mobile piston 48.

In the preferred embodiment, the movement of the plate 45 continues until a microswitch 69 is reached; he microswitch is provided at the bottom of the structure 41 to lock the motor 66 (figs. 1 and 4) and, if it were necessary, to reverse its rotation movement; this operation The expulsion stage ends.

Once the stage of expulsion, the infusion cycle may start again after a first stage of elementary movement of the plate 45 in the piston direction 43 stationary adapted to carry sequentially to a resting position at springs 71, which connect the plate 45 and the chamber 46, and the spring 81 associated with the 48 piston mobile. Obviously, as you can easily understand an expert in the field, take the springs 71 that connect the plate 45 and chamber 46 to the rest position corresponds to make the ejection device 49 change from the position of expulsion to the resting position.

The machine and the infusion unit have described above taking as reference a type machine vertical in which the dispensing tap is connected to the stationary piston As you can easily understand the subject matter experts, the dispensing tap can also connect to the mobile piston and the boiler to the stationary piston and the liquid flow can be reversed compared to what is described previously.

In addition, nothing prevents the machine from having a different orientation to the vertical, since the manipulation is performed in any case by motorized elements or elastic

The infusion unit has been described by taking as reference an elastic connection between the movable plate and the mobile camera formed through elastic elements arranged in triangular way. Obviously, in other embodiments the number of elastic elements can be less than or greater than three and the position of the elastic elements can be centrobaric with respect to the plate and chamber, solution that is preferred for requirements associated with mechanical wear of moving parts, or it may not be centrobaric.

In addition, in the description, the elements elastic, which connect the plate and the chamber, and the element elastic, associated with the piston, have been described as springs of cylindrical pressure Obviously, the elastic elements too they can be of a different type and they can also understand, by example, without departing from the scope of the above description, materials that have a reversible elasticity, such as rubber.

In the preferred embodiment, the device expulsion comprises a resistance arm and a spatula connected in such a way to obtain a movement substantially Horizontal of the spatula. Obviously, in other embodiments, the arm and spatula can be connected differently, however obtaining the same result, or they may also be rigidly connected.

In the description of the machine and the unit infusion, it is expected that the top of the plate that moves away from the Stationary piston is determined by a microswitch. Obviously, in other embodiments, the stop may also determined by measuring a possible overcurrent absorbed by the engine or differently, without departing from the scope of the previous description. Obviously, the same considerations to determine the completion of the stage Pressing

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References cited in the description

This list of references cited by the Applicant is only for the convenience of the reader. Not a part of the European patent document. Although it has been taken special careful in the compilation of references, cannot be excluded errors or omissions and the EPO rejects all responsibility to this respect.

Patent documents cited in the description

EP 0528758 A [0003]

EP 0756843 A [0013]

EP 0298544 A [0013]

EP 0299399 A [0013]

Claims (12)

1. Infusion unit for the preparation of infusions, in particular espresso coffee, by means of powders infusion, which includes

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a stationary piston (43), a movable chamber (46) and a piston (48) mobile concentric to the mobile camera, which can act jointly for the preparation of said infusion by means of said powders and to generate a pill of powders used, being said movable piston (48) arranged to move with respect to the mobile chamber (46) for preparing said powder tablet used for expulsion from said infusion unit by means of a mechanically activated ejection device (49);

characterized because

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bliss infusion unit comprises a plate (45) associated with means (55, 65, 66) of movement arranged to move said license plate,

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bliss chamber comprises at least one elastic connection element (71) that It has a certain stiffness and is ready to connect said chamber with said plate in order to induce the movement of said chamber together with said plate and to allow movement relative of said chamber with respect to said plate, and

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saying ejection device is mechanically activated by the relative movement of said plate with respect to said camera.

2. Infusion unit (14) according to claim 1, characterized in that said movement means (55, 65, 66) are centrobaric with respect to said plate (45) and because said chamber (46) is located centrally with respect to to said plate. 3. Infusion unit (14) according to claim 1 or 2, characterized in that said ejection device (49) is shaped as a lever having

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a actuating arm (93) pivoting towards said chamber by a first pivot (96) and towards said plate by a second pivot (95), and

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a resistance arm (97) arranged to eject said tablet from powders used

4. Infusion unit (14) according to claim 3, characterized in that said first pivot (96) is the fulcrum of said lever. 5. Infusion unit (14) according to claim 3, characterized in that said chamber comprises a first cavity (76) orthogonal to the movement of said chamber, and said resistance arm (97) comprises a second cavity (107) longitudinal to the arm of resistance, and because said resistance arm is associated with a spatula (99) having sliding means arranged to slide in said first cavity (76) and in said second cavity (107) and to determine a rectilinear movement of said spatula. 6. Infusion unit (14) according to any one of the preceding claims, characterized in that said mobile piston (48) comprises

-

to the less an elastic element (81) shaped to allow said relative movement of said mobile piston with respect to the chamber mobile to prepare said powder tablet used for its expulsion of said infusion unit, presenting said at least an elastic element (81) a stiffness less than the stiffness of said at least one elastic connecting element (71).

7. Infusion unit (14) according to any one of the preceding claims, characterized in that said movement means (65) comprises stop means arranged to block the movement of said mobile piston (48), whereby said piston (48) mobile is arranged to move with respect to the mobile camera (46). 8. Infusion unit (14) according to any one of the preceding claims, characterized in that said at least one elastic connecting element (71) comprises three elastic elements (71) arranged triangularly and having the mobile chamber as a barycenter. 9. Infusion unit (14) according to any one of the preceding claims, characterized in that it is an infusion unit of vertical type. 10. Machine for the preparation of infusions, in particular espresso coffee, by means of an infusion powder, which It comprises at least one infusion unit according to the claims 1 to 9, at least one boiler (12) connected to the input of said at least one infusion unit and arranged to send a liquid for the preparation of said infusions to said at least one infusion unit, and at least one tap (15) of dispensing connected to the output of said at least one unit of infusion and ready to dispense said infusion. 11. Procedure for manufacturing a unit of infusion for the preparation of infusions, in particular coffee express, by means of an infusion powder, which comprises the stage from

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provide a piston (43) stationary, a mobile chamber (46) and a mobile piston (48) concentric to the mobile camera, ready to act together for the preparation of said infusion by means of said powders and for generate a pill of used powders, said arrangement being arranged mobile piston (48) to move relative to the mobile chamber for preparing said powder tablet used for its expulsion from said infusion unit by means of an ejection device (49) mechanically activated; Y

characterized by the stages of

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provide a plate (54) associated with movement means (55, 65, 66) arranged to move said license plate,

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provide at least one element (71) elastic connection that has a certain stiffness to connect said camera with said plate to induce the movement of said camera together with said plate and to allow movement relative of said chamber with respect to said plate, and

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provide an ejection device arranged to be mechanically activated by movement relative of said plate with respect to said chamber.

12. Method according to claim 11, characterized by the step of

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provide means of detention associated with said means (65) of movement and arranged to block the movement of said mobile piston (48), so that said mobile piston (48) is arranged to move with respect to the mobile camera (46).